Veigar doesn't really have any tough to learn mechanics. Just E and hole to stun, then W, Q, R. It is really simple. The only "skill" required it csing with Q and poking and csing at the same time with one Q (Hitting a Q on a minion then go through and hit the laner for harrass). Just follow the build or go morellenomicon first idc. Just have an example build like that.

TL;DR: Learn to CS with Q, farm, know what to build for the math up, and land your E.

<This is my first guide before the new runes and masteries come out so there is no reason to keep updating or add more to this guide, but thank you.>